1. Field of the Invention
The present invention relates to a recording and reproducing apparatus suitable for recording and reproducing data having a large capacity in real time and a file managing method using the apparatus.
2. Description of the Related Art
Recently, a tape drive apparatus (such as a tape streamer drive apparatus) and a hard disk apparatus can record the video image of a movie, etc. as image data. Operation for recording video data requires a recording medium capable of real-time recording and reproduction and of recording of a large capacity. Then, recording operation is performed by individually using a hard disk apparatus using a high-speed accessible magnetic disk as a recording medium and a tape drive apparatus using a magnetic tape having a large recording capacity as a recording medium.
If a large capacity of data can be ensured in the hard disk apparatus, the overall file can be recorded. In this case, any desired portion in the file can be fast accessed. However, if a capacity to record the overall file cannot be ensured, for example, a method is adopted whereby the head portion (cue data) in the file of the video data is recorded in the hard disk apparatus and the whole or the remaining data is recorded to the magnetic tape by the tape drive apparatus. For this method, it is considered that the capacity of the hard disk apparatus smaller than that of the magnetic tape is effectively used. Consequently, when a user searches desired video data, the head of the file can be fast accessed. After that, the desired video data is reproduced from the tape drive apparatus.
However, when recording is performed by using the tape drive apparatus, a large capacity of data, for example, several ten gigabytes (GB) can be recorded depending on the capacity of the magnetic tape as a recording medium. However, the tape drive apparatus reproduces data by sequentially accessing one magnetic tape, thus taking a long time for search and reproduction of the cue data. Therefore, if considering time necessary for searching and reproduction of the cue data, the tape drive apparatus is not suitable to continuously record and reproduce, in particular, a video image in real time.
In the hard disk apparatus, the fast access is possible and data can be recorded and reproduced in the real time manner. However, the hard disk apparatus has a problem that a storage capacity is smaller than that of the magnetic tape and it is not sufficient to record the video image having a large capacity. If only the head portion (cue data) is recorded, the kind of video data is increased and, then, there is a problem that a recording capacity becomes insufficient and satisfactory data cannot be stored.
In order to overcome the above-mentioned problems, according to the present invention, there is provided a recording and reproducing apparatus comprising: changer means for selecting and carrying a plurality of tape cassettes that are arranged therein and accommodate magnetic tapes on which a plurality of recording areas on a predetermined unit are formed; tape drive means for loading the tape cassette carried by the changer means and for recording and reproducing the magnetic tape accommodated in the tape cassette; hard disk drive means at least having a buffer area for recording and reproducing data by the tape drive means and cue data area for recording cue data as part of a file recorded to the magnetic tape; recording area managing means for managing each recording area of the magnetic tape accommodated in the tape cassette arranged in the changer means as a continuously formed area; recording state managing means for managing the recording states of the file in the magnetic tape, the buffer area, and a cue data area; file recording control means for controlling operation for recording the file in the magnetic tape and the buffer area; cue data recording control means for forming cue data of the file and for recording the formed data to the cue data area; and erasing control means for controlling operation for erasing the file recorded or the cue data the file.
According to the present invention, a recording and reproducing apparatus can be realized to enable the recording and reproduction of a large capacity of data in real time by using the capacity of a magnetic tape loaded by changer means and fast access of hard disk means.
According to the present invention, the capacity of the hard disk apparatus can be effectively used in accordance with using frequency of a file, and data of a file with high using frequency can be reproduced by fast access.